U.S. patent number 6,019,022 [Application Number 09/231,946] was granted by the patent office on 2000-02-01 for multi-purpose screwdriver.
This patent grant is currently assigned to Snap-on Tools Company. Invention is credited to Mark A. Dotson.
United States Patent |
6,019,022 |
Dotson |
February 1, 2000 |
Multi-purpose screwdriver
Abstract
A combination screwdriver, scraper and prybar has a handle with
an elongated shank terminating in a multi-function blade. The blade
has opposed, flat, planar blade faces converging toward and joined
by a distal planar end surface which intersects and is
perpendicular to the longitudinal axis of the shank. The blade
faces are respectfully inclined to the axis at substantially three
degrees and substantially seven degrees. The shank may be square or
circular in transverse cross-section and, if square, opposed sides
of the shank lie in planes perpendicular to the blade faces.
Inventors: |
Dotson; Mark A. (Watauga,
TN) |
Assignee: |
Snap-on Tools Company (Kenosha,
WI)
|
Family
ID: |
26760498 |
Appl.
No.: |
09/231,946 |
Filed: |
January 15, 1999 |
Current U.S.
Class: |
81/436;
7/165 |
Current CPC
Class: |
B25B
15/00 (20130101); B25B 15/007 (20130101); B25B
15/02 (20130101) |
Current International
Class: |
B25B
15/02 (20060101); B25B 15/00 (20060101); B25B
015/00 () |
Field of
Search: |
;7/105,165,166 ;81/436
;30/169 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Smith; James G.
Attorney, Agent or Firm: Emrich & Dithmar
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. provisional application
Ser. No. 60/078,410, filed Mar. 18, 1998 and U.S. provisional
application Ser. No. 60/078,893, filed Mar. 19, 1998.
Claims
I claim:
1. A multi-function hand tool comprising:
a handle, and
an elongated blade coupled to the handle and having a longitudinal
axis,
said blade having first and second opposed, converging, planar
blade faces respectively disposed on opposite sides of the axis and
respectively inclined to the axis at different first and second
angles, wherein neither of said blade faces intersects the
axis.
2. The tool of claim 1, wherein said first and second blade faces
respectively have different lengths.
3. The tool of claim 1, and further comprising an elongated shank
coupling said blade to the handle.
4. The tool of claim 3, wherein said shank is substantially square
in transverse cross section.
5. The tool of claim 4, wherein said shank has opposed side
surfaces which respectively lie in planes which are perpendicular
to said first and second blade faces.
6. The tool of claim 3, wherein said shank is substantially
circular in transverse cross section.
7. The tool of claim 3, and further comprising first and second
indicia on said shank adjacent to said blade and respectively
designating said first and second blade faces thereof.
8. A multi-function hand tool comprising:
a handle, and
an elongated blade coupled to the handle and having a longitudinal
axis,
said blade having first and second opposed, converging, planar
blade faces respectively disposed on opposite sides of the axis and
respectively inclined to the axis at different first and second
angles, wherein each of said first and second angles is less than
10.degree..
9. The tool of claim 8, wherein said first angle is less than
5.degree..
10. The tool of claim 9, wherein said first and second angles are
respectively substantially 3.degree. and 7.degree..
11. A multi-function hand tool comprising:
a handle, and
an elongated blade coupled to the handle and having a longitudinal
axis,
said blade having first and second opposed, converging, planar
blade faces respectively disposed on opposite sides of the axis and
respectively inclined to the axis at different first and second
angles,
said blade having a distal end surface intersecting the axis and
interconnecting said blade faces.
12. The tool of claim 11, wherein said blade has flat side surfaces
perpendicular to said blade faces.
13. The tool of claim 12, wherein said side surfaces are parallel
to each other and perpendicular to said end surface.
14. The tool of claim 12, and further comprising an elongated shank
coupling said blade to the handle, said side surfaces being spaced
apart a distance greater than the thickness of said shank.
15. The tool of claim 14, wherein said side surfaces are
respectively joined to said shank by tapered shoulders.
16. The tool of claim 11, wherein said end surface is a
substantially flat planar surface disposed substantially
perpendicular to the axis.
17. The tool of claim 11, wherein said end surface intersects the
axis at a point closer to one of said blade faces than to the
other.
18. The tool of claim 11, wherein each of said first and second
angles is less than 10.degree..
19. The tool of claim 18, wherein said first angle is substantially
3.degree. and said second angle is substantially 7.degree..
Description
BACKGROUND OF THE INVENTION
The present invention relates generally to hand tools and, in
particular, to multi-function tools. The invention has particular
application to a driver-type tool, such as a screwdriver, adapted
for additional uses.
It is known to provide a variety of different types of generally
flat-bladed hand tools for different application purposes, such as
screwdrivers, scrapers, prybars and the like. Typically, each such
tool has a blade and a shank specifically designed for the
particular application for which the tool is intended. Each such
tool works well for its intended purpose, but requires that the
user maintain a collection of several tools. While multi-function
tools have heretofore been provided, their designs have not been
optimal for screwdriver scraping and prying applications.
SUMMARY OF THE INVENTION
It is a general object of the invention to provide an improved hand
tool which avoids the disadvantages of prior tools while affording
additional structural and operating advantages.
An important feature of the invention is the provision of a hand
tool which is adapted for multiple uses.
In connection with the foregoing feature, a further feature of the
invention is the provision of a driver-type hand tool which is
suitable for multiple uses, including driving, prying and
scraping.
Still another feature of the invention is the provision of a hand
tool of the type set forth, which is of relatively simple and
economical construction.
Certain ones of these and other features of the invention are
attained by providing a multi-function hand tool comprising: a
handle, and an elongated blade coupled to the handle and having a
longitudinal axis, said blade having first and second opposed
converging planar blade faces respectively disposed on opposite
sides of the axis and respectively inclined to the axis at
different first and second angles.
The invention consists of certain novel features and a combination
of parts hereinafter fully described and illustrated in the
accompanying drawings, it being understood that various changes in
the details may be made without departing from the spirit, or
sacrificing any of the advantages of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
For the purpose of facilitating an understanding of the invention,
there is illustrated in the accompanying drawings a preferred
embodiment thereof, from an inspection of which, when considered in
connection with the following description, the invention, its
construction and operation, and many of its advantages should be
readily understood and appreciated.
FIG. 1 is a side elevational view of a hand tool constructed in
accordance with and embodying the features of the present
invention;
FIG. 2 is a view in vertical section taken along the line 2--2 in
FIG. 1;
FIG. 3 is an enlarged, fragmentary, top plan view of the shank and
blade of the tool of FIG. 1;
FIG. 4 is a view in vertical section taken along the line 4--4 in
FIG. 3;
FIG. 5 is a fragmentary, bottom plan view of the shank and blade of
FIG. 3;
FIG. 6 is a further enlarged, fragmentary view of the blade of the
tool of FIG. 1;
FIG. 7 is a view similar to FIG. 1 of a tool with a circular
cross-section shank; and
FIG. 8 is a view in vertical section taken along the line 8--8 in
FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1-6 of the drawings, there is illustrated a
screwdriver-type hand tool, generally designated by the numeral 10,
constructed in accordance with the present invention. The tool 10
has an elongated metal shank 11, which is substantially square in
transverse cross-section, fixed at one end to a handle 12, which
may be provided with a frictional overgrip sleeve (not shown). The
handle 12 is preferably formed of a suitable plastic material, such
as cellulose acetate, while the overgrip is formed of a suitable
flexible and resilient material, such as rubber. The shank 11 has
opposed parallel top and bottom surfaces 13 and 14 and opposed
parallel side surfaces 15 and 16.
The shank 11 is provided at its opposite end with a working blade
20, which has a widened portion 21 which is wider than the
thickness of the shank 11 and is joined thereto by curved shoulder
portions 22. The widened portion 21 has substantially flat, planar,
opposed faces 23 and 24 which terminate at a narrow, distal end
surface 25, which may be a generally rectangular, planar surface,
and which joins the faces 23 and 24 to form a screwdriver tip. More
specifically, the face 23 is designed as a scraper face and is
inclined at a relatively small angle "a" to the longitudinal axis X
of the shank and blade. The face 24 is designed as a prybar face,
and is inclined at a larger angle "b" to the axis X.
It can be seen that the blade faces 23 and 24 are, respectively,
disposed on opposite sides of the axis X, and it will be
appreciated that the relative lengths of the faces 23 and 24 will
depend upon their distances from the axis X at the end surface 25.
Thus, if the axis X passes through the center of the end surface
25, the ratio of the lengths of the faces 23 and 24 will be
inversely proportional to the ratio a/b. Preferably, the end
surface 25 is offset so that it intersects the axis X closer to the
face 24 than to the face 23, as illustrated in FIG. 6, so that the
lengths of the faces 23 and 24 are more nearly equal.
In formation of the blade 20, the end of the shank 15 is flattened
to produce the faces 23 and 24 and then the opposite sides are
preferably milled to provide substantially parallel, flat side
surfaces 26 and 27, which are respectively substantially parallel
to the shank side surfaces 15 and 16 and perpendicular to the blade
end surface 25.
In operation, the shallow-angled face 23 is designed to facilitate
use of the tool 10 as a scraper and, in use, would typically be
disposed downwardly against the surface being scraped. The more
steeply inclined face 24 is designed to facilitate use of the tool
10 as a prybar. Also, the widened portion 21 of the blade 20 may be
used as a standard flat head screwdriver in the normal manner. If
desired, an indicium 28, such as the letter "P", may be imprinted
on one side of the shank 11 at the end of the scraper face 23 to
indicate that that side is to be disposed upwardly when the tool is
used as a prybar. The shank 11 may be provided on the opposite side
with an indicium 29, such as the letter "S", to indicate that that
side is to be up when the tool is used as a scraper.
The tool 10 has a shank thickness A, a blade end width B, a blade
tip thickness C, a shank length D, an exposed shank length E and an
overall tool length F. The tool 10 may be provided in a variety of
sizes, the dimensions A-F for a number of such sizes being
illustrated, by way of example, in Table I.
TABLE I ______________________________________ Shank Shank Total
Stock Wide Thick Length Exposed Length
______________________________________ .250 .250 .037 7 4 6 .250
.312 .046 9 6 8 .312 .375 .060 11 8 11 .375 .500 .075 11 8 11 .375
.625 .100 13 10 13 A C D E F
______________________________________
The shank 11 and the handle 12 of the tool 10 are designed to meet
the various strength requirements for the several intended uses of
the tool. Thus, the handle 12 may be designed to have a tensile
strength in the range 3,000-6,000 psi, an elongation at breakage of
50-100% and a compressive strength at yield in the range of
2,000-5,000 psi. The shank 11 is preferably formed of a suitable
steel, such as a chrome-vanadium steel, and may be designed to have
a tensile strength in the range 90,000-200,000 psi and a yield
strength in the range 50,000-200,000 psi. The shank 11 may be
suitably heat treated to provide the requisite hardness, while at
the same time providing the necessary ductility when the tool is
used as a prybar and the necessary strength and wearability when
used has a fastener driver or scraper.
While the shank 11 is preferably formed of square stock to
facilitate use as a prybar and to permit the use of a wrench at any
point along the shank to apply additional torque, it will be
appreciated that other cross-sectional shapes could be utilized.
Referring to FIGS. 7 and 8, there is illustrated a hand tool 30
which is substantially the same as the hand tool 10, except that it
has a shank 31 which is circular in transverse cross-section. This
shape of shank is the simplest and least expensive to
manufacture.
While the handle 12 is preferably formed of cellulose acetate,
other suitable plastic materials, such as polypropylene materials
or PVC could be used and, while the overgrip, if used, is
preferably formed of rubber, other materials such as soft
polyurethane or the like, could also be utilized.
While particular embodiments of the present invention have been
shown and described, it will be obvious to those skilled in the art
that changes and modifications may be made without departing from
the invention in its broader aspects. Therefore, the aim in the
appended claims is to cover all such changes and modifications as
fall within the true spirit and scope of the invention. The matter
set forth in the foregoing description and accompanying drawings is
offered by way of illustration only and not as a limitation. The
actual scope of the invention is intended to be defined in the
following claims when viewed in their proper perspective based on
the prior art.
* * * * *